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  <div class="section" id="allocating-objects-on-the-heap">
<span id="allocating-objects"></span><h1>Allocating Objects on the Heap<a class="headerlink" href="#allocating-objects-on-the-heap" title="永久链接至标题">¶</a></h1>
<dl class="function">
<dt id="c._PyObject_New">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">_PyObject_New</code><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em><span class="sig-paren">)</span><a class="headerlink" href="#c._PyObject_New" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em></dd></dl>

<dl class="function">
<dt id="c._PyObject_NewVar">
<a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject">PyVarObject</a>* <code class="descname">_PyObject_NewVar</code><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em>, Py_ssize_t<em>&nbsp;size</em><span class="sig-paren">)</span><a class="headerlink" href="#c._PyObject_NewVar" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em></dd></dl>

<dl class="function">
<dt id="c.PyObject_Init">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Init</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*op</em>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Init" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>Initialize a newly-allocated object <em>op</em> with its type and initial
reference.  Returns the initialized object.  If <em>type</em> indicates that the
object participates in the cyclic garbage detector, it is added to the
detector's set of observed objects. Other fields of the object are not
affected.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_InitVar">
<a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject">PyVarObject</a>* <code class="descname">PyObject_InitVar</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject">PyVarObject</a><em>&nbsp;*op</em>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em>, Py_ssize_t<em>&nbsp;size</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_InitVar" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>This does everything <a class="reference internal" href="#c.PyObject_Init" title="PyObject_Init"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Init()</span></code></a> does, and also initializes the
length information for a variable-size object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_New">
TYPE* <code class="descname">PyObject_New</code><span class="sig-paren">(</span>TYPE, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_New" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Allocate a new Python object using the C structure type <em>TYPE</em> and the
Python type object <em>type</em>.  Fields not defined by the Python object header
are not initialized; the object's reference count will be one.  The size of
the memory allocation is determined from the <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_basicsize" title="PyTypeObject.tp_basicsize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_basicsize</span></code></a> field of
the type object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_NewVar">
TYPE* <code class="descname">PyObject_NewVar</code><span class="sig-paren">(</span>TYPE, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em>, Py_ssize_t<em>&nbsp;size</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_NewVar" title="永久链接至目标">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Allocate a new Python object using the C structure type <em>TYPE</em> and the
Python type object <em>type</em>.  Fields not defined by the Python object header
are not initialized.  The allocated memory allows for the <em>TYPE</em> structure
plus <em>size</em> fields of the size given by the <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_itemsize" title="PyTypeObject.tp_itemsize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_itemsize</span></code></a> field of
<em>type</em>.  This is useful for implementing objects like tuples, which are
able to determine their size at construction time.  Embedding the array of
fields into the same allocation decreases the number of allocations,
improving the memory management efficiency.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Del">
void <code class="descname">PyObject_Del</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*op</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Del" title="永久链接至目标">¶</a></dt>
<dd><p>Releases memory allocated to an object using <a class="reference internal" href="#c.PyObject_New" title="PyObject_New"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_New()</span></code></a> or
<a class="reference internal" href="#c.PyObject_NewVar" title="PyObject_NewVar"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_NewVar()</span></code></a>.  This is normally called from the
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> handler specified in the object's type.  The fields of
the object should not be accessed after this call as the memory is no
longer a valid Python object.</p>
</dd></dl>

<dl class="var">
<dt id="c._Py_NoneStruct">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> <code class="descname">_Py_NoneStruct</code><a class="headerlink" href="#c._Py_NoneStruct" title="永久链接至目标">¶</a></dt>
<dd><p>Object which is visible in Python as <code class="docutils literal notranslate"><span class="pre">None</span></code>.  This should only be accessed
using the <a class="reference internal" href="none.html#c.Py_None" title="Py_None"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_None</span></code></a> macro, which evaluates to a pointer to this
object.</p>
</dd></dl>

<div class="admonition seealso">
<p class="first admonition-title">参见</p>
<dl class="last docutils">
<dt><a class="reference internal" href="module.html#c.PyModule_Create" title="PyModule_Create"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyModule_Create()</span></code></a></dt>
<dd>To allocate and create extension modules.</dd>
</dl>
</div>
</div>


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